A local tax and advisory firm built around one promise.
Our mission is simple: ensuring each taxpayer pays the least amount of tax, within the bounds of the tax code, while providing premium service to create a great client experience.
Serving Contra Costa County families and businesses since day one.
Same team year over year — not a rotating cast of preparers.
Client portal for secure documents, e-signature, and messaging.
Built in Concord. For Contra Costa County.
API Accounting, Tax & Advisory, Inc. has been serving Contra Costa County from our Concord office for 30+ years. We started as a small family business and grew — one referral at a time — into a full-service firm covering accounting, payroll, entity, tax planning, IRS representation, and financial planning.
Along the way we've stayed intentionally small enough that clients still work with the same people year after year. We know our clients' businesses, their families, and their goals — and we plan accordingly.
A clear, predictable client experience.
We listen first. A no-pressure conversation to understand your situation.
You get transparent pricing and scope in writing before any work begins.
Secure document exchange, e-signature, and messaging — all in one place.
Year-round communication, frequent check-ins, and annual planning.
Experienced leadership. Client-centered.
Kelby brings over 12 years of experience in tax planning, financial services, and business leadership. His approach centers on personalized service, proactive tax strategy, and long-term financial planning. He holds a B.S. from California State Polytechnic University, Pomona, with a background in finance, real estate, and law.
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Caesar brings over 13 years of experience in tax planning, financial analysis, and high net worth tax strategy, with a focus on complex situations involving foreign trusts, foreign income, and estate tax exposure. He holds a Master of Taxation from the University of Cincinnati and earned his CPA in 2022.
Enrolled Agent. Coming from a finance and tech background, Andrew brings a modern view on tax strategies with a deep understanding of the needs of business owners and business development. He works primarily with individuals and S-corporations. Andrew has been with the firm since 2024.
Ron has been with API for nearly 20 years, working almost exclusively with small business owners. His practice centers on restaurants, gas stations, and real estate, where he handles tax planning, entity structures, and the returns that follow from them.
Yesenia has been with API for over a decade, with nearly 20 years representing taxpayers before the IRS, the Franchise Tax Board, the California Department of Tax and Fee Administration, and the EDD. Her tax resolution services include audits, tax liens, levies, penalties, installment agreements, OICs, and more.
Let's talk about your situation.
Whether you're a growing business or a family with complex returns, the first call is on us.